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(No Model.)

G. W. JOHNSTON.

TYPE WRITING MACHINE. No. 340,882. Patented Apr. 27, 1886.

u. Firms, Photo-MW. Walh'mgtao. o. c.

UNITED STATES PATENT OFFICE.

GEORGE NV. JOHNSTON, OF BOONVILLE, MO., ASSIGNOR OF ONE-HALF TO OOTAVIUS KNIGHT AND HARRY E. KNIGHT, BOTH OF WASHINGTON, D. O.

TYPE-WRITING MACHINE.

SPECIFICATION forming part of Letters Patent No. 340,882, dated April 2'7, 1886.

Serial No. 178,435. (No model.)

To aZZ whom, it may concern.-

Be it known that I, GEORGE W. JOHNSTON, a citizen of the United States, residing at Boonville, in the county of Cooper and State of 5 Missouri, have invented certain new and use ful Improvements in TypeWVriting Machines, of which the following is a specification.

M y present improvement relates to typewriting machines of the type of the caligraph,

IO having a feed-rack divided longitudinally, the two parts moving relatively to each other every time the paper-carriage is fed forward one space. These two racks or two parts of a rack are customarily connected together by pins I 5 and slots, the extent of motion of one rack on the other being determined by the distance between the pins and ends of the slots. By varying the length ofthe slots a greater or less feed-motion is obtained at every stroke,

the amount of motion necessarily depending on the width of the teeth of the rack.

I have conceived the idea of providing means for varying at will the amount of feed of the carriage for any one machine by lengthening the slots of the rack suifieiently to allow for the greatest length of feed desired-say, three teeth of the rack-and providing a movable I stop which maybe made at will to cover more or less or none of the slot, and thus stop the rack after it has made a stroke equal to the width of one, two, or other number of teeth. The value of such an improvement is principally in writing matter which it is desired to spread out to render more legible,which,with

the machine ordinarily in use, must be done by striking the spacing-key one or more times between every two type-keys.

In order that my invention may be more fully understood, I will proceed to describe it with reference to the accompanying drawings,

in which- Figure I is a rear view of a feed-rack with one form of my invention applied thereto. Fig. II is a similar view showing a modified form of the invention. Fig. III is a similar view showing still another modification.

1 represents the rear or exterior rack of a caligraph, it being connected to the interior rack, so as to have capacity for motion thereon by means of pins or screws 2 and slots 3 in customary manner. The slots 3 are in my improvement, however, made of extra length, corresponding to the extreme limit of stroke it is desired to give the racl; with each depression of the spacing or other key. To fix 5 the stroke so that one, two, or other desired number of teeth of the rack shall be passed,

I provide a stop, 4-, which may be placed over any of the slots of the rack; but I show it located over an end slot. In Fig. I a sliding 6o stop having a toothed or notched edge adapted to be engaged by the nose of spring 5 is employed. A thumb-piece, 6, 011 the stop per mits its adjustment in its guides 7, so as to cover more or less of the slot 3. In Fig. II a pivoted stop is employed turning on a pin, 8, and resting when covering the end of the slot on a projection, 9, from the rack. Being thrown over back of its pivot-pin, however,

it hangs vertically beyond the reach of the pin 2, and so does not interfere with the motion of the rack. This form of pivotal stop is adapted to but a single change of length of feed. In Fig. III, however, I have shown a circular stop pivoted eccentrically, so that it may cover any desired amount of the slot, as

in the form shown in Fig. I. A spring-dog,

5, and a ratchet are also employed in this case, for retaining the stop to set position.

Having thus described my invention, the 83 following is what I claim as new therein and desire to secure by Letters Patent:

1. The combination of a fixed rack, a sliding rack, elongated slot-and-pin connection between the racks, and a stop adjustable over 85 a slot limiting the movement of the pin therein and fixing the stroke of the sliding rack.

2. In combination with a movable feed-rack and an adjustable stop mounted thereon and extending over a slot therein for limiting its 0 mot-ion, a spring-dog for retaining said stop in adjusted position.

3. In combination with a movable feed-rack,

a pivoted stop thereon and the stop-pins,

GEORGE IV. JOHNSTON.

\Vitnesses:

J OHN S. J rnnv, N. ALZ. 

